Clube de Futebol Os Unidos, or more commonly Unidos de Lisboa, is a Portuguese football club established as Grupo Desportivo CUF de Lisboa (commonly known as CUF Lisboa, with CUF standing for the company Companhia União Fabril) in 1936.

It was during this period that the club had its most successful spell, playing three consecutive seasons, from 1940–41 to 1942–43, in the Primeira Divisão, when qualification was obtained through the district championships.

In 1944, the prohibition of corporate names ended, and Unidos reverted to CUF Lisboa.

The club dissolved in 1947 for lack of a ground, but returned to the Lisbon FA district championships in 1954, under the Unidos de Lisboa name,[2] seemingly choosing to ignore its CUF connections.

The last senior team to play was on the 2008–09 in the Lisbon FA First Division (district second tier).